Therapy unit



March 1963 H. E. KOERNER ETAL 3,

THERAPY UNIT Filed Nov. 28, 1958 INVENTORS Harry E. Koerner 8 BY efl W. Vaughn WWW/L Ever WITNESSES ATTORNEY United States This invention relates to a therapy unit and more par ticularly to an apparatus for radiation therapy employing a source of penetrating radiation such as an artificially radioactive isotope, cobalt 60, for example, or an X-ray tube.

Radiation therapy units have heretofore been proposed which deal with the problem of reducing the patients skin dosage by concentrating a beam of radiation at a treatment point while either the patient, in a sitting position in a rotatable chair, is turned in the presence of the beam, or the source of radiation is caused to move around the patient while in a reclining position. Diifering circumstances tend to dictate the use of one or the other of these techniques.

In view of the foregoing remarks, it is an object of the present invention to provide a radiation therapy unit which may be operated in either of the above modes.

Radiation therapy units heretofore proposed of the type in which the radiation source is rotated about a hori z ontal axis along which the patient lies are characterized by considerable bulk which necessitates dedication of considerable floor space for its accommodation.

Accordingly it is another object of the present invention to provide a relatively compact less bulky radiation therapy unit of this type.

A further object of the invention is to provide a basic arrangement for mounting of the radiation source and accommodation of the patient which affords flexibility in choice of location and arrangement of counterweight and shielding for the radiation beam.

Other objects and advantages of the invention will become apparent from the following description of preferred embodiments of such invention when taken in connection with the accompanying drawings in which:

FIG. 1 is a perspective view of the novel therapy unit embodying the invention as employed for radiation therapy while the patient is in a horizontal'reclining position;

FIG. 2 is a side elevation view partly in outline and partly in section showing internal structural details of the therapy unit as well as an alternate arrangement for counterbalancing the source holder of the apparatus of FIG. 1;

FIG. 3 is a similar view of a further alternate arrangement for combined beam shielding and source holder counterbalancing; and

FIG. 4 is a front elevation view which illustrates an alternate method for employment of the novel therapy unit while the patient is in a sitting position.

Referring to the various figures in the drawing, in accord with the present invention, the novel therapy unit essentially comprises a housing 1 having a circular patientaccommodating opening 2 extending horizontally therethrough, a rotatable support ring 3 encircling the patient accommodating opening 2, and a source holder 4 carried by the support ring 3 for rotary movement about the axis or opening 2.

According to other and alternate features of the invention, the source holder support ring 3 may carry a combined counterweight and beam-absorbing shield 5 disposed opposite to the source holder 4, as shown in FIG. 1; the walls and floor of the room may be relied on for shielding and the ring 3 may carry a counterweight 6, oppositely-arranged with respect to source holder 4 and atent ice disposed at the rear of the housing 1, as shown in FIG. 2; or as shown in FIG. 3, the ring 3 may carry two oppositely-arranged source holders 4, each. of which counterbalances and acts as the beam absorber shield for the other.

According to a preferred feature embodied in the invention is a simplified means in the form of horizontallyspaced-apart support-and-drive rollers 7, FIG. 2, in contact with a bottom surface of the ring 3, which provides both a vertical support for the ring and its burden as well as a friction coupling between such ring and a driving motor 8. The support ring 3, in the presence of the load which it carries, is maintained in a vertical attitude in supporting contact with the support-and-drive rollers 7 through the medium of a plurality of constraining or guide rollers 9 within the housing 1 which are spacedapart circumferentialwise of such support ring in rolling contact with opposite annular faces thereof.

Also disposed within the housing 1 are the necessary structural members 15 to which outer cover members 16 are attached and which carry the necessary support bearings for the respective shafts 17 of the support-and-drive rollers 7 as well as for the shafts 18 of the guide rollers 9. The driving motor 8, preferably also within the housing 1 is shown operatively connected to the support-anddrive rollers 7 through the medium of a chain-and sprocket arrangement 19 linking the motor shaft to the roller shaft 17. A variable speed reducer (not shown) may be interposed between the motor 8 and chain drive 19 so that signals from a control (not shown) may be imposed on the reducer to effect a change of speed at the will of an operator.

To provide for attachment of the source holder 4 and the counterweight and beam-absorbing shield of the FIG. 1 structure, or the arrangement of dual source holders 4 of the FIG. 3 arrangement, the support ring 3 is provided with a hollow cylindrical portion 25 which extends outwardly from the front face of the housing 1 and is provided with the necessary support arms 26 to which the source holder or holders 4 are attached at a pivotal connection 27 as Well as with the necessary support ribs 28 (FIG. 1) for attachment to the counterweight-and beam-absorbing shield 5.

In similar fashion, the counterweight 6 of the FIG. 2 arrangement may be attached to the ring 3 through a hollow cylindrical portion 29 extending backwardly through opening 2 into attachment with such counterweight at the rear of the housing 1.

In the arrangement of FIG. 2, with the counterweight 6 for the source holder 4 being located to the rear of housing 1, the therapy unit will be in balance and may simply rest on a suitable support floor Without necessitating attachment to any external member in order to remain upright.

In the arrangements such as shown in FIGS. 1 and? in which the center of gravity of the source holder weight, counterweights etc. is located beyond the front face of the housing 1, an anchor member 30 attached to structural members 15 is mounted flush with the upper surface 31 of the floor to prevent the therapy unit from tipping while providing an unobstructed floor surface at the front of such unit.

It will be apparent that without departing from certain desirable features of the invention, the source holder 4 may contain an X-ray tube, but preferably will take the form of a heavily shielded radioactive source material holder as shown herein and which is described in detail in copending US. patent applications by Robert L. Guentner and Edward P. Moran, Serial No. 748,350, filed iuly 14, 1958 and by Eugene P. Thomas, Serial No. 760,791, filed September 12, 1958, now Patent No. 3,048,- 70l, both applications being assigned to the assignee of the present application. In such form of exemplified holder, the therapy unit of the invention is afforded further advantages in flexibility of opertaion resultant from structural and function features of such source holder as including a circular beam emergence portion 32 into the center of which a-radioactive source material capsule (not shown herein) may be actuated from a repose position in a shielded body portion 33 for registry with beam emergence cone means 34 and which may be rotated about its axis 35 relative to body portion 33 to orient the cone means 34 in any desired direction radialwise of such axis. The pivotal connection 27 joins the body portion 33 of holder 4 to the arms 26 along an axis perpendicular to the axis 35 of beam emergence portion 32 of such holder, so that rocking movement of the holder 4 about the axis of pivotal connection 27 affords still further freedom for orientation of the beam emergence cone means 34.

Operation Referring particularly to FIG. 1, in operation of the novel therapy unit for radiation treatment of a patient while in a horizontal reclining position, the patient will be lying on a portable treatment table 40 which may be wheeled into position at the front of the therapy unit and anchored thereto by means of a coupling member 41 adapted to lock the table against unintentional movement following set-up and therapy. The patient supporting portion 42 of table 40 as particularly adapted for employment with the therapy unit is movable longitudinally of the table relative to the anchored base portion 43 of such table by suitable actuating mechanism (not shown). By such means the patient may be moved to obtain alignment of the beam emergence cone means 34 with the portion of the patients body to undergo radiation treatment. By virtue of the horizontal through-opening 2 in the housing 1, the patient supporting portion 42 of the treatment table or/ and the patient may extend into such opening.

During such locating of the patient with respect to the beam emergence cone means 34, the source holder 4 may be located in any of its infinite number of circumferential positions about the opening 2, although convenience may dictate a preferred position, such as directly above the patient as shown in FIG. 1. The holder 4 will be oriented with respect to the axis of its pivotal connection 27 to arms 26 such that the cone means 34 will point radially inward toward the patient. Radiation therapy may then be commenced as a static proposition, for example, in which the source holder 4 remains stationary; in such instance the treatment zone need not necessarily be located along the axis of opening 2 in the housing 1, and under certain circumstances the beam emergence cone means 34 may even be brought into close proximity of the patient. In rotational therapy the patient will be positioned such that the treatment area will lie along the horizontal axis of the opening 2 and the source holder 4 will be turned slowly at a controlled rateabout such axis by operation of the motor 8 which will turn the. support ring 3 through the medium of support-and-drive rollers 7 in frictionally-driving supporting contact with such ring.

Rendering the source holder 4 effective and ineffective to emit radiation is accomplished pneumatically in a manner set forth in the aforementioned US. patent application, and aside from providing for accommodation within the housing 1 of an air compressor, air storage tank, and retractable air supply hose (none of which are shown herein), the present invention is not concerned with such operational control of the source holder per se.

In all variants of the counterweight arrangements illustrated in FIGS. 1, 2 and 3 it will be appreciated that the counterweights will turn with the ring 3 in unison with the source holder and permit the assemblage to be turned by motor 8 with a minimum amount of effort.

In the arrangement of FIG. 1 it will be appreciated that member will remain opposite to source holder 1 in all rotary positions of holder 1 circumferentialwise of the opening 2 to both maintain the assemblage in balance as well as to absorb radiation transmitted through the patient.

In the FIG. 3 showing, the oppositely-arranged source holders 4 serve to counterbalance one another as well as absorb the radiation which passes through the patient, and the duality may be taken advantage of either during static treatment, as in selection of one or the other holder for attacking the treatment area from opposite directions without disturbing the patients position or moving the source holders from a given set-up position, or both holders may be rendered effective simultaneously in either static or rotary treatment to reduce treatment time.

In employing the therapy unit for treatment of a patient in a sitting position, FIG. 4, a rotary treatment chair 50 may be placed in front of the housing 1 in substitution for the treatment table 46 and the source holder 4 be brought into three oclck or nine oclock position with respect to the opening 2. Height adjustments to obtain alignment of the beam emergence cone means 34 with the zone of the patient to be treated is preferably obtained by adjustments of the chair 50, although angulation of the beam emergence portion 32 will permit the source holder 4 to be raised and lowered to some extent out of the three or nine oclock position by rotary movement of the ring 3.

Although the invention has been described in connection with certain preferred embodiments, it should be understood that changes may be made and equivalents substituted without departing from the spirit and scope of the invention.

We claim as our invention:

1. Radiation therapy apparatus comprising, an upright housing member having a through opening extending horizontally therethrough which accommodates projection of a patient support table thereinto, a radioactive source material holder and an oppositely-arranged counterweight-and-shield mounted on said upright housing member for rotary movement about the horizontal axis of said through opening in a plane of revolution located exclusively without and adjacent to one end thereof to render such source material holder accessible to both a patient lying on said table as well as a patient sitting in front of such housing, said housing member being constructed and arranged for floor mounting without floor surface obstruction in the region thereof beneath said source material holder and said counterweight-and-shield.

2. Radiation therapy apparatus comprising a floormounted upright housing member having an opening extending horizontally therethrough which accommodates projection of a patient support table thereinto, a rotatable ring member encircling said opening, a radioactive source material holder and an opposite counterweightand-shield carried by said ring for rotation therewith about the axis of said opening in a plane of revolution located exclusively without and adjacent to one end thereof, rotary bearing means disposed within said housing for rotary support of said ring, of said source material holder, and of said counterweight-and-shield, an anchor means secured to said housing member for preventing tilting of same and affording an unobstructed floor surface beneath said source material holder and said counterweight-andshield.

3. Radiation therapy apparatus comprising a floor mounted upright housing member having an opening extending horizontally therethrough, a rotatable ring member encircling said opening, a radioactive source material holder and a counterweight-and-shield oppositely arranged on said ring for movement therewith in a plane of revolution located exclusively without and adjacent to one end of said opening, roller members within said housing vertically supporting said ring in frictional driving contact therewith, guide roller means within said housing in contact with side faces of said ring to maintain same in proper vertical attitude, motor means within said housing for rotating said roller members to effect turning movement of said ring, and anchor means secured to said housing member for preventing tilting of same and aitording an unobstructed floor surface beneath said source material holder and said counter-Weight-and-radiation shield.

4. Radiation therapy apparatus comprising a floormounted upright housing member having an opening extending horizontally therethrough which accommodates projection of a patient table thereinto, a ring member encircling said opening and supported for rotary movement about the axis of such opening by bearing members disposed within said housing, a radioactive source material holder and an opposite counterWeight-and-radiation shield mounted on said ring for disposition exclusively adjacent to and Without said opening and for rotation about the axis thereof, and anchor means secured to said housing member for preventing tilting of same and affording an unobstructed floor surface beneath said source material holder and said counterweight-and-radiation shield.

5. The combination as set forth in claim 4, wherein said counterweight-and-radiation shield is constituted by a second radioactive source material holder, and wherein the two holders each have means directing beam emergence one toward the other, whereby one source holder counterbalances the other and substantially absorbs radiation emerging from the other, and whereby radiation treatment of a patient between such source holders is in tensified and treatment time thereby reduced.

6. Radiation therapy apparatus comprising a floormounted upright housing member having an opening extending horizontally therethrough, a radioactive source material holder and an opposite counterweight-and-radiation shield mounted on said upright housing member for rotatable movement about the horizontal axis of said opening in a plane of revolution located exclusively without and adjacent to one end thereof, means for removably coupling a patient support table to said housing for anchoring same relative to said source material holder while affording its removal for substitution of a treatment chair, and anchor means secured to said housing member for preventing tilting of same and affording an unobstructed floor surface beneath said source material holder and said counterweight-and-radiation shield.

References Cited in the file of this patent UNITED STATES PATENTS 2,781,454 Green et al. Feb. 12, 1957 2,818,510 Verse Dec. 31, 1957 2,890,349 Huszar June 9, 1959 FOREIGN PATENTS 396,177 Germany May 27, 1924 713,055 Great Britain Aug. 4, 1954 

1. RADIATION THERAPY APPARATUS COMPRISING, AN UPRIGHT HOUSING MEMBER HAVING A THROUGH OPENING EXTENDING HORIZONTALLY THERETHROUGH WHICH ACCOMMODATES PROJECTION OF A PATIENT SUPPORT TABLE THEREINTO, A RADIOACTIVE SOURCE MATERIAL HOLDER AND AN OPPOSITELY-ARRANGED COUNTERWEIGHT-AND-SHIELD MOUNTED ON SAID UPRIGHT HOUSING MEMBER FOR ROTARY MOVEMENT ABOUT THE HORIZONTAL AXIS OF SAID THROUGH OPENING IN A PLANE OF REVOLUTION LOCATED EXCLUSIVELY WITHOUT AND ADJACENT TO ONE END THEREOF TO RENDER SUCH SOURCE MATERIAL HOLDER ACCESSIBLE TO BOTH A PATIENT LYING ON SAID TABLE AS WELL AS A PATIENT SITTING IN FRONT OF SUCH HOUSING, SAID HOUSING MEMBER BEING CONSTRUCTED AND ARRANGED FOR FLOOR MOUNTING WITHOUT FLOOR SURFACE OBSTRUCTION IN THE REGION THEREOF BENEATH SAID SOURCE MATERIAL HOLDER AND SAID COUNTERWEIGHT-AND-SHIELD. 